As the world rapidly advances, the convenience offered by plastics continues to overshadow the environmental consequences they carry. Scientists are now turning their focus to microplastics, minuscule fragments of plastic that persist in marine ecosystems for decades. Recent research conducted by a collaboration of researchers from Japan and Thailand has revealed a concerning trend: microplastics are infiltrating coral anatomy, raising alarms about the wider implications of pollution in the oceans. This pivotal study sheds light on the pervasive threat to coral reefs and highlights the urgent need for deeper inquiry into the dynamics of plastic interaction within marine life.
Microplastics come from a variety of sources, including larger discarded plastic debris that breaks down into smaller pieces, as well as microbeads found in personal care products. According to estimates, every year, between 4.8 to 12.7 million tons of plastic waste makes its way into the ocean. Despite efforts to track plastic pollution, approximately 70% of it remains inexplicably absent from pollution surveys—a phenomenon dubbed the “missing plastic problem.” The research team proposes that coral may serve as an unintentional repository for these tiny pollutants, thus playing a critical role in understanding oceanic plastic dispersal.
Facing the challenge of studying microplastics within coral, researchers from Kyushu University’s Research Institute for Applied Mechanics (RIAM) and Thailand’s Chulalongkorn University embarked on a groundbreaking endeavor. Their efforts led to the establishment of the Center for Ocean Plastic Studies in 2022, which aims to address the pressing concerns of plastic waste in marine ecosystems.
To investigate the impact of microplastics on coral, the team collected a range of 27 coral samples from four different species along the coast of Si Chang Island, Thailand. This locale was selected due to its unique reef flats and anthropological significance. Utilizing a novel detection technique, the researchers devised a method to extract and analyze microplastics from the three key anatomical layers of coral: the surface mucus, the tissue, and the skeleton. Chemical washes allowed for the disintegration of these layers, enabling researchers to filter and quantify the microplastic particles present in each segment.
The results were striking. A total of 174 microplastic particles were identified, predominantly measuring between 101 to 200 micrometers, akin to the diameter of a human hair. The distribution of these particles revealed significant findings: 38% resided in the coral’s surface mucus, 37% were found in the skeleton, and 25% permeated the coral tissue itself. Notably, the most prevalent types of microplastics discovered were nylon, polyacetylene, and polyethylene terephthalate (PET)—substances that have become ubiquitous in human-produced waste.
These findings imply that coral may act as a sink for microplastics, drawing them from the surrounding ocean and thus potentially providing an explanation for the elusive missing plastic. Similar to how trees absorb carbon dioxide, the corals’ ability to sequester plastic raises critical questions about the cumulative effects on coral health and broader marine ecosystems.
The presence of microplastics within corals is not just an isolated discovery; it reverberates throughout the marine food web and ecosystems. The study emphasizes the need for further research to comprehend the long-term transport and deposition of microplastics in various marine species. Coral reefs, known as the rainforests of the sea, are already under significant stress from climate change, ocean acidification, and overfishing. The addition of microplastic contamination could exacerbate these challenges, posing further risks to the viability of these vital ecosystems.
Considering that corals can preserve their skeletal structures for extended periods even after death, deposited microplastics may persist in these areas for centuries. The implications of this endurance could be far-reaching, warranting a more comprehensive approach to exploring the potential impacts on marine survival and biodiversity.
These remarkable revelations prompt an urgent call to action for researchers and environmentalists alike. Assistant Professor Suppakarn Jandang and Professor Atsuhiko Isobe stress the necessity for expanded global studies to evaluate the extent of microplastic contamination across diverse coral species. Understanding the intricate details of how microplastics affect coral health and the broader reef community is vital for developing strategies to combat marine pollution effectively.
As human reliance on plastics continues unabated, the hope lies in harnessing this knowledge for policy action, conservation efforts, and public awareness campaigns. If comprehensive efforts are not undertaken to address the growing plastic crisis, the beauty and biodiversity of the world’s coral reefs may face unprecedented challenges—a fate that is too dire to ignore.